An electric motor creates a mechanical force from electromagnetic current. An alternating current (AC) electric motor (AC motor) generally comprises a stationary stator and a rotor. The stationary stator generally comprises electrical wire coils supplied with alternating current producing a rotating magnetic field. The rotor is attached to an output shaft that is given a torque by the rotating magnetic field.
A type of electric motor is a reluctance motor that generates torque through magnetic reluctance. A reluctance motor induces non-permanent magnetic poles on a ferromagnetic rotor. Existing reluctance motors generally have a high torque ripple, where a difference between maximum and minimum torque during one revolution is high when operated at low speed.
There is a need for electro-mechanical motors that are small, low weight, high torque, and can operate at low speed. There is a further need for such electro-mechanical motors to provide actuation that can be low vibration, jam free and/or tolerant, and provide high holding load capability.